Trailer lights flash

[Kevin0311]

2019 High country when connected to a trailer the light quickly flash every 10 seconds when truck is off with or without parking brake set, anyone else have this issue?

[OnTheReel]

Actually a feature, not an issue. It’s a part of the trailer anti-theft system. It pulses the trailer lights to check for load. The idea is if someone unhooks your trailer, it’ll notice the lack of current draw and trigger the alarm.

[crankman]

Interesting mine only flash if i hit the FOB to lock the truck. Why would you want your trailer lights flashing all the time day or night while it parked. Don't sound right.

[steve841]

It's a known issue ... . and yes, it's associated with the security.

 

Quite simply, they don't know how to fix it.

[Opiedeegs]

https://techlink.mynetworkcontent.com/?p=11176
Check this out


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[Kevin0311]

Interesting 

the theft system is off in the trailer app but still flashes and the link above say “may flash” even when off

seems odd but I guess I will have to deal with it 

[Rsktm300xcw]

That link is very informative and would have been very helpful to me about a month ago. I through a ton of trial and error figured out that my trailer lights need to have just the right amount of load for everything to work correctly. A little tip, if you have LED lights and are seeing error being detected by your trailer light test adding a resistor to the circuit fixed my brake light problem. On my running lights circuit my trailer had 17 incandescent lights and they would all turn on for 1 second and then turn off every time I tried them. The trailer test showed a running light problem. I swapped all 17 out for LEDs to reduce the load and that seems to have solved my problem. So it is very important to reach the right  balance for the trailer light control module to see enough load to know that the light is working but not to overload so the module shuts the circuit off. Can be tricky. There is also an update out to "reflash" the module. I dont remember the number but it listed near the end of the cold weather electrical problem thread. My local dealer did the update as well. So far dont seem to have problems. Waiting for first long trip with the trailer to see if it is all solved.

[Rsktm300xcw]

The name of the other thread I was referring to is cold weather errors ( trailer connections). Lst post was Apri 8.

[Zpittman]

They still haven’t fixed this on 2020 models. Just bought one and hooked my 2016 year trailer up to it. Flickers and pulses alot when parked and off. Haven’t tried it yet with trails theft mode off. 

[Smoothbassman]

Yeah.

Mine was doing that also today. I thought it was just me. It seemed to go out completely after a few minutes.

I'll keep an eye on it.

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[Rsktm300xcw]

Does anybody remember the old days when a flashing led on their dash would tell a would be thief that the security system was armed?

[davester]

5 hours ago, Rsktm300xcw said:

Does anybody remember the old days when a flashing led on their dash would tell a would be thief that the security system was armed?

No.

[Smoothbassman]

Does anybody remember the old days when a flashing led on their dash would tell a would be thief that the security system was armed?

Old days. It's still like that today!

My 2019 has that same flashing light.

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[Cole_dog]

So has anyone ever got this problem resolved? My trailer behind my 2019 Sierra is doing it also. I called my dealer and they said they have never heard of this before. I’m 1 1/2hrs from my dealer so I was hoping there was a fix I could do. 

Edited October 8, 2019 by Cole_dog

[Rsktm300xcw]

If you read the link posted in the beginning of this topic you will see that there is nothing to fix. The flashing is supposed to happen. It's part of the system. I believe it is for security. The truck " checks" to see if the trailer is still connected.